CVE-2018-3711
Denial of Service vulnerability with large JSON payloads in fastify
Fastify node module before 0.38.0 is vulnerable to a denial-of-service attack by sending a request with "Content-Type: application/json" and a very large payload.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
Fastify node module before 0.38.0 is vulnerable to a denial-of-service attack by sending a request with "Content-Type: application/json" and a very large payload.
- Record
CVE-2018-3711- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:N/I:N/A:P - Weakness
- CWE-770
- Updated
- 2026-11-02
CVE List No score
Fastify node module before 0.38.0 is vulnerable to a denial-of-service attack by sending a request with "Content-Type: application/json" and a very large payload.
- Record
CVE-2018-3711- Weakness
- CWE-770
- Updated
- 2026-11-02
EUVDEUVD-2018-0299 No score
Fastify node module before 0.38.0 is vulnerable to a denial-of-service attack by sending a request with "Content-Type: application/json" and a very large payload.
- Record
EUVD-2018-0299- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-mq6c-fh97-4gwv
Denial of Service vulnerability with large JSON payloads in fastify
Affected versions of fastify are vulnerable to a denial of service when processing a request with Content-Type set to application/json and a very large payload.
Recommendation
Update to version 0.38.0 or later.
- Record
GHSA-mq6c-fh97-4gwv- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-400, CWE-770
- Updated
- 2026-11-02
OSV
Fastify node module before 0.38.0 is vulnerable to a denial-of-service attack by sending a request with "Content-Type: application/json" and a very large payload.
- Record
CVE-2018-3711- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVGHSA-mq6c-fh97-4gwv
Denial of Service vulnerability with large JSON payloads in fastify
Affected versions of fastify are vulnerable to a denial of service when processing a request with Content-Type set to application/json and a very large payload.
Recommendation
Update to version 0.38.0 or later.
- Record
GHSA-mq6c-fh97-4gwv- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-400, CWE-770
- Updated
- 2026-11-02
Affected products
Affected packages
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2018-3711 is a high vulnerability (CVSS 7.5) in Fastify, published June 7, 2018. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.77%, the 78th percentile. Fixed in fastify 0.38.0.